The wall of a liquid-to-gas heat exchanger has a surface area on the liquid side of 1.8 m2 (0.6m × 3m) with a heat transfer coefficient of 255 W/(m2 K). On the other side of the heat exchanger wall flows a gas, and the wall has 96 thin rectangular steel fins 0.5 cm thick and 1.25 cm high [k = 3 W/(m K)]. The fins are 3 m long and the heat transfer coefficient on the gas side is 57 W/(m2 K). Assuming that the thermal resistance of the wall is negligible, determine the rate of heat transfer if the overall temperature difference is 38?C.GIVENThe wall of a heat exchanger has 96 fins on the gas sideSurface area on the liquid side (AL) = 1.8 m2 (0.6 m × 3 m)Heat transfer coefficient on the liquid side (hcL) = 255 W/(m2 K)The wall has 96 thin steel fins 0.5 cm thick and 1.25 cm highThermal conductivity of the steel (k) = 3 W/(m K)Fin length (w) = 3 m, Fin height (L) = 1.25 cm = 0.0125 mFin thickness (t) = 0.5 cm = 0.005 mHeat transfer coefficient on the gas side (hcg) = 57 W/(m2 K)The overall temperature difference (??T) = 38?CASSUMPTIONSThe thermal resistance of the wall is negligibleThe heat transfer through the wall is steady stateThe thermal conductivity of the steel isconstant

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L=.0125 m -t= 0.005 m Gas Liquld A Section of the Wall